This is a 3 year revised application that proposes to provide a working model using antibodies, Fab's/F(ab')2's or scFvs to block sporozoite (from P. gallinaceum) invasion of salivary glands in mosquitoes (A. aegypti). The ultimate goal is to be able to insert genes for these scFv's into mosquitoes using recombinant methods so that the mosquitoes will not be suitable hosts for sporozoite invasion and transmission. The idea is that results from these research projects will be relatively easily transferred to the P. falciparum sporozoites and their vectors, anopholine mosquitoes.